Abstract: A waveguide photodetector includes a first contact layer of a first conductivity type, a waveguide layer, and a second contact layer of a second conductivity type that are sequentially formed on the semiconductor substrate. The waveguide layer includes a first cladding layer of the first conductivity type disposed on a side of the first contact layer, a second cladding layer of the second conductivity type disposed on a side of the second contact layer, and the core layer disposed between the first cladding layer and the second cladding layer. The core layer includes a light absorption layer and an impurity-doped light absorption layer that has a higher concentration of a p-type impurity than that of the light absorption layer and is disposed on a side of a light incident face.

Abstract: Provided are a photodetector, a manufacturing method thereof, and a lidar system. A photosensitive region of the photodetector is circular and has a diameter range of 100-300 ?m. Compared with a conventional photodetector having a photosensitive region with a diameter of 50 ?m, the photodetector of the present invention can have a detection range greater than 200 m, responsivity greater than 20 A/W and a dark current less than 10 nA.

Abstract: An avalanche photodiode detector is provided. The avalanche photodiode detector comprises an absorber region having an absorption layer for receiving incident photons and generating charged carriers; and a multiplier region having a multiplication layer; wherein the multiplier region is on a mesa structure separate from the absorber region and is coupled to the absorber region by a bridge for transferring charged carriers between the absorber region and multiplier region.

Abstract: A dichromatic photodiode and method for dichromatic photodetection are disclosed. A wide bandgap junction comprises a lattice matched junction operable to detect a first light spectrum. A narrow bandgap junction is coupled to the wide bandgap junction, and comprises a photodiode structure. The narrow bandgap junction is operable to detect a second light spectrum.

Abstract: Photodetectors operable to achieve multiplication of photogenerated carriers at ultralow voltages. Embodiments include a first p-i-n semiconductor junction combined with a second p-i-n semiconductor junction to form a monolithic photodetector having at least three terminals. The two p-i-n structures may share either the p-type region or the n-type region as a first terminal. Regions of the two p-i-n structures doped complementary to that of the shared terminal form second and third terminals so that the first and second p-i-n structures are operable in parallel. A multiplication region of the first p-i-n structure is to multiply charge carriers photogenerated within an absorption region of the second p-i-n structure with voltage drops between the shared first terminal and each of the second and third terminals being noncumulative.

Abstract: The inventive concept provides avalanche photo diodes and methods of manufacturing the same. The avalanche photo diode may include a substrate, a light absorption layer formed on the substrate, a clad layer formed on the light absorption layer, an active region formed in the clad layer, a guard ring region formed around the active region, and an insulating region formed between the guard ring region and the active region.

Abstract: Apparatuses and systems for photon detection can include a first optical sensing structure structured to absorb light at a first optical wavelength; and a second optical sensing structure engaged with the first optical sensing structure to allow optical communication between the first and the second optical sensing structures. The second optical sensing structure can be structured to absorb light at a second optical wavelength longer than the first optical wavelength and to emit light at the first optical wavelength which is absorbed by the first optical sensing structure. Apparatuses and systems can include a bandgap grading region.

Abstract: The inventive concept provides avalanche photo diodes and methods of manufacturing the same. The avalanche photo diode may include a substrate, a light absorption layer formed on the substrate, a clad layer formed on the light absorption layer, an active region formed in the clad layer, a guard ring region formed around the active region, and an insulating region formed between the guard ring region and the active region.

Abstract: A two-dimensional, temporally modulated electromagnetic wavefield, preferably in the ultraviolet, visible or infrared spectral range, can be locally detected and demodulated with one or more sensing elements. Each sensing element consists of a resistive, transparent electrode (E) on top of an insulated layer (O) that is produced over a semiconducting substrate whose surface is electrically kept in depletion. The electrode (E) is connected with two or more contacts (C1; C2) to a number of clock voltages that are operated synchronously with the frequency of the modulated wavefield. In the electrode and in the semiconducting substrate lateral electric fields are created that separate and transport photogenerated charge pairs in the semiconductor to respective diffusions (D1; D2) close to the contacts (C1; C2).

Abstract: Photodetectors operable to achieve multiplication of photogenerated carriers at ultralow voltages. Embodiments include a first p-i-n semiconductor junction combined with a second p-i-n semiconductor junction to form a monolithic photodetector having at least three terminals. The two p-i-n structures may share either the p-type region or the n-type region as a first terminal. Regions of the two p-i-n structures doped complementary to that of the shared terminal form second and third terminals so that the first and second p-i-n structures are operable in parallel. A multiplication region of the first p-i-n structure is to multiply charge carriers photogenerated within an absorption region of the second p-i-n structure with voltage drops between the shared first terminal and each of the second and third terminals being noncumulative.

Abstract: Photodiode devices with GeSn active layers can be integrated directly on p+ Si platforms under CMOS-compatible conditions. It has been found that even minor amounts of Sn incorporation (2%) dramatically expand the range of IR detection up to at least 1750 nm and substantially increases the absorption. The corresponding photoresponse can cover of all telecommunication bands using entirely group IV materials.

Abstract: An avalanche photodetector comprising a multiplication layer formed of a first material having a first polarization; the multiplication layer having a first electric field upon application of a bias voltage; an absorption layer formed of a second material having a second polarization forming an interface with the multiplication layer; the absorption layer having a second electric field upon application of the bias voltage, the second electric field being less than the first electric field or substantially zero, carriers created by light absorbed in the absorption layer being multiplied in the multiplication layer due to the first electric field; the absorption layer having a second polarization which is greater or less than the first polarization to thereby create an interface charge; the interface charge being positive when the first material predominately multiplies holes, the interface charge being negative when the first material predominately multiplies electrons, the change in electric field at the inte

Abstract: An avalanche photodiode structure, to a method of fabricating an avalanche photodiode structure, and to devices incorporating an avalanche photodiode structure. The avalanche photodiode structure comprises a Ge doped region having a first polarity; a GaAs doped region having a second polarity opposite to the first polarity; and an undoped region between the Ge doped region and the GaAs doped region forming a heterojunction; wherein the undoped region comprises Ge and AlxGa1-xAs.

Abstract: A single carrier avalanche photodiode (200) comprising a p-doped absorption layer (213), an unintentionally doped avalanche multiplication layer (203) and an n-doped collector layer (211) and a method of manufacturing said avalanche photodiode. The absorption layer is doped at a level that allows the photodiode to operate as a single carrier device. Therefore total delay time of the device is mainly dependent on electrons. The collector layer is in charge of reducing capacitance in the device. A built-in field layer (212) of n+? doped material may be provided between the two layers in order to improve the injection of electrons in the collector layer.

Abstract: An avalanche photodiode including a first electrode; and a substrate including a first semiconductor layer of a first conduction type electrically connected to the first electrode, in which at least an avalanche multiplication layer, a light absorption layer, and a second semiconductor layer of a second conduction type with a larger band gap than the light absorption layer are deposited on the substrate. The second semiconductor layer is separated into inner and outer regions by a groove formed therein, the inner region electrically connected to a second. With the configuration, the avalanche photodiode has a low dark current and high long-term reliability. In addition, the outer region includes an outer trench, and at least the light absorption layer is removed by the outer trench to form a side face of the light absorption layer. With the configuration, the dark current can be further reduced.

Abstract: A light emitting device comprising a transparent substrate; a layer of conducting material in contact with the transparent substrate; a self-assembled monolayer bonded to the layer of conducting material; one or more light emitting polymer layers in electron contact to the self-assembled monolayer; and a reflective metal layer in electron contact with the light emitting polymer layer is provided. The light emitting device provided gives enhanced performance as compared to currently available devices. Also provided is a self-assembled monolayer having the formula: R2—R3—Y where Y is a group capable of electron contact with a light emitting polymer, R3 contains a conjugated group, and R2 is a group capable of bonding to a conducting material.

Abstract: Provided is an avalanche photodetector with an integrated micro lens. The avalanche photodetector includes a light absorbing layer on a semiconductor substrate, an amplification layer on the light absorbing layer, a diffusion layer within the amplification layer, and the micro lens disposed corresponding to the diffusion layer. The micro lens includes a first refractive layer and a second refractive layer having a refractive index less than that of the first refractive layer.

Abstract: A single-photon detector is disclosed that provides reduced afterpulsing without some of the disadvantages for doing so in the prior art. An embodiment of the present invention provides a stimulus pulse to the active area of an avalanche photodetector to stimulate charges that are trapped in energy trap states to detrap. In some embodiments of the present invention, the stimulus pulse is a thermal pulse.

Abstract: Embodiments relate to an image sensor and a method of forming an image sensor. According to embodiments, an image sensor may include a first substrate and a photodiode. A circuitry including a metal interconnection may be formed on and/or over the first substrate. The photodiode may be formed over a first substrate, and may contact the metal interconnection. The circuitry of the first substrate may include a first transistor, a second transistor, an electrical junction region, and a first conduction type region. The first and second transistors may be formed over the first substrate. According to embodiments, an electrical junction region may be formed between the first transistor and the second transistor. The first conduction type region may be formed at one side of the second transistor, and may be connected to the metal interconnection.

Abstract: The invention offers a photodetector that has an N-containing InGaAs-based absorption layer having a sensitivity in the near-infrared region and that suppresses the dark current and a production method thereof. The photodetector is provided with an InP substrate 1, an N-containing InGaAs-based absorption layer 3 positioned above the InP substrate 1, a window layer 5 positioned above the N-containing InGaAs-based absorption layer 3, and an InGaAs buffer layer 4 positioned between the N-containing InGaAs-based absorption layer 3 and the window layer 5.

Abstract: A semiconductor waveguide based optical receiver is disclosed. An apparatus according to aspects of the present invention includes an absorption region including a first type of semiconductor region proximate to a second type of semiconductor region. The first type of semiconductor is to absorb light in a first range of wavelengths and the second type of semiconductor to absorb light in a second range of wavelengths. A multiplication region is defined proximate to and separate from the absorption region. The multiplication region includes an intrinsic semiconductor region in which there is an electric field to multiply the electrons created in the absorption region.

Abstract: A transmitted light absorption/recombination layer, a barrier layer, a wavelength selection/absorption layer, and an InP window layer having a p-type region are supported by an n-type substrate and arranged in that order. Light with a wavelength of 1.3 ?m reaches the wavelength selection/absorption layer through the InP window layer. Then, the light is absorbed by the wavelength selection/absorption layer and drawn from the device as an electric current signal. Light with a wavelength of 1.55 ?m reaches the transmitted light absorption/recombination layer through the barrier layer. Then, the light is absorbed by the transmitted light absorption/recombination layer, generating electrons and holes. These electrons and holes recombine with each other and, hence, disappear.

Abstract: The invention relates to an avalanche photodiode having enhanced gain uniformity enabled by a tailored diffused p-n junction profile. The tailoring is achieved by a two stage doping process incorporating a solid source diffusion in combination with conventional gas source diffusion. The solid source diffusion material is selected for its solubility to the dopant compared to the solubility of the multiplication layer to dopant. The solid source has a diameter between the first and second diffusion windows. Thus, there are three distinct diffusion regions during the second diffusion. The dopant in the multiplication layer at the edge region, the dopant from the solid source material with a relatively higher dopant concentration (limited by the solubility of the dopant in the solid source material) at the intermediate region, and the central region exposed to an infinite diffusion source from the solid source material as it is continually charged with new dopant from the external gas source.

Abstract: The organic TFT includes: a gate electrode; source and drain electrodes insulated from the gate electrode; an organic semiconductor layer insulated from the gate electrode and electrically connected to the source and drain electrodes; an insulating layer insulating the gate electrode from the source and drain electrodes and the organic semiconductor layer; and a self-assembly monolayer (SAM) included between the insulating layer and the organic semiconductor layer. A compound forming the SAM has at least one terminal group selected from the group consisting of an unsubstituted or substituted C6-C30 aryl group and an unsubstituted or substituted C2-C30 heteroaryl group. The organic TFT is formed by forming the above-described layers and forming the SAM on the insulating layer before the organic semiconductor layer and source and drain electrodes are formed.

Abstract: A single-photon avalanche detector is disclosed that is operable at wavelengths greater than 1000 nm and at operating speeds greater than 10 MHz. The single-photon avalanche detector comprises a thin-film resistor and avalanche photodiode that are monolithically integrated such that little or no additional capacitance is associated with the addition of the resistor.

Abstract: A semiconductor photo detector of the present invention includes a layer structure, having a selective etching layer of a first-type conductivity, a field-relaxing layer of the first-type conductivity, a multiplier layer, a field-relaxing layer of a second-type conductivity, a light absorption layer of the second-type conductivity, a selective etching layer of the second-type conductivity, a buffer layer of the second-type conductivity, a contact layer of the second-type conductivity, and an electrode in the side of the second-type conductivity, which are sequentially deposited over a semiconductor substrate, and having a second mesa formed on the semiconductor substrate and a first mesa formed on the second mesa, wherein the first mesa includes the buffer layer of the second-type conductivity, the contact layer of the second-type conductivity, and the electrode in the side of the second-type conductivity, wherein the second mesa includes the layer of the first-type conductivity, the multiplier layer, the lig

Abstract: A single-photon detector is disclosed that provides reduced afterpulsing without some of the disadvantages for doing so in the prior art. An embodiment of the present invention provides a stimulus pulse to the active area of an avalanche photodetector to stimulate charges that are trapped in energy trap states to detrap. In some embodiments of the present invention, the stimulus pulse is a thermal pulse.

Abstract: In a semiconductor photo-detecting element (an avalanche photodiode), a high-sensitivity element is obtained by incorporating a multiplication layer having high-performance multiplication characteristics. By using a structure which reduces an electric field applied to an etching stopper layer, it is possible to use a multiplication layer having higher-performance multiplication characteristics (a multiplication layer which performs multiplication with a high electric field). The first method to realize this is to use a conductivity type multiplication layer. The second method is to use a structure in which a field buffer layer of the second conductivity type is incorporated. As a result of the use of these methods, a structure which applies an electric field lower than the multiplier electrical field to the etching stopper layer is obtained.

Abstract: An avalanche photodiode (APD) includes an anode layer, a cathode layer, an absorption layer between the anode layer and the cathode layer, a first multiplying stage between the absorption layer and the cathode layer, a second multiplying stage between the first multiplying stage and the cathode layer, and a carrier relaxation region between the first and second multiplying stages. Each multiplying stage includes, in the direction of drift of electrons, a first layer that is doped with acceptors, a second layer that is substantially undoped, a third layer that is doped with acceptors, a fourth layer that is substantially undoped, and a fifth layer that is doped with donors.

Abstract: A planar avalanche photodiode includes a small localized contact layer on the top of the device produced by either a diffusion or etching process and a semiconductor layer defining a lower contact area. A semiconductor multiplication layer is positioned between the two contact areas and a semiconductor absorption layer is positioned between the multiplication layer and the upper contact layer. The photodiode has a low capacitance and a low field near the edges of the semiconductor multiplication and absorption layers.

Abstract: A photodetector includes a charge carrier collector and a charge carrier concentrator that redirects onto the collector charge carriers that are not initially headed towards the collector.

Abstract: A photodetector for use at wavelengths of 2 ?m and longer has an intersubband absorption region to provide absorption at wavelengths beyond 2 ?m, integrated with an avalanche multiplier region to provide low-noise gain. In one particular design, the intersubband absorption region is a quantum-confined absorption region (e.g., based on quantum wells and/or quantum dots).

Abstract: An integrated thermal imager for detecting combined passive LWIR or MWIR radiation of a scene and active SWIR radiation of a laser source is described The imager includes a two-dimensional focal plane array (2D-FPA) constituted by an assembly of voltage tunable photodetectors. Each voltage tunable photodetector integrates a quantum well infrared photodetector (QWIP) together with a heterojunction bipolar phototransistor (HBPT), thereby forming a pixel element in the 2D-FPA.

Abstract: The present invention provides a heterojunction photodiode which includes a pn or Schottky-barrier junction formed in a first material region having a bandgap energy Eg1. When reverse-biased, the junction creates a depletion region which expands towards a second material region having a bandgap energy Eg2 which is less than Eg1. This facilitates signal photocurrent generated in the second region to flow efficiently through the junction in the first region while minimizing the process-related dark currents and associated noise due to near junction defects and imperfect surfaces which typically reduce photodiode device performance. The heterojunction photodiode can be included in an imaging system which includes an array of junctions to form an imager.

Abstract: An GaN light emitting diode (LED) having a nanorod (or, nanowire) structure is disclosed. The GaN LED employs GaN nanorods in which a n-type GaN nanorod, an InGaN quantum well and a p-type GaN nanorod are subsequently formed in a longitudinal direction by inserting the InGaN quantum well into a p-n junction interface of the p-n junction GaN nanorod. In addition, a plurality of such GaN nanorods are arranged in an array so as to provide an LED having much greater brightness and higher light emission efficiency than a conventional laminated-film GaN LED.